Wind power facilities including a wind turbine mounted on top of a support structure such as a tower typically include internal cabling that runs from a nacelle of the turbine to the bottom of the tower and beyond. The cabling may include, for example, power transmission lines to deliver electrical power produced by the turbine generator to an external power grid, internal power cables for powering auxiliary systems, and data cables carrying control data and/or measurement data between the nacelle and remote systems, for example a SCADA (supervisory control and data acquisition) system.
Large wind power facilities cannot be transported to a site in an assembled state, and so must be erected at the site. This entails installing and connecting the internal cabling at the site, which is difficult, time-consuming, and potentially hazardous; particularly in the case of offshore wind power facilities. There is therefore a desire to ease the process of cable installation to reduce the time required to perform this task.
It is known to use a rigid curved steel tube, or ‘J-tube’, disposed within the tower of the wind power facility to act as a guide and support for a transmission line that is drawn up through the J-tube until reaching a transition piece that ultimately supports the line. Electrical connections to the line can then be made as required. The J-tube ensures that bending of the transmission line is controlled, thereby preventing damage to the line during and after installation. EP2696123 discloses a development on this theme, in which a flexible reinforced protective tube is used to protect the transmission line, the line and the protective tube being lifted together to the transition piece.
While such arrangements ease moving the transmission line into position, they do not help with the complicated task of making electrical connections to components of the wind turbine. Wind power facilities may have one or more cable bundles, each potentially containing dozens of individual cables. For example, bulky high voltage power transmission cables are often divided into bundles of multiple cables to improve flexibility. Connecting each of these cables within the nacelle represents a considerable burden on the installer.
It is against this background that the invention has been devised.